Griff



(I Vo Model.) 4

- W. M HOFFMAN,

ABRADING SHOEI'OR/TRUING'UP GAR WHEELS.

UNIT D ST TES wILiJI ii M. HOFFMAN,

PATENT Urrrcs.

AB RADJNG-SHOE FOR TRUING UP CAR-WHEELS.

SPECIFICATION forming part of Letters Patent Nb. 605,056, dated May 31, 1898.

Application filed March 1,1897. Renewed March 17, 1898. Serial No. 674,262. (No model.)

To all whom it may con-061w:

Be it known that 1, WILLIAM M. llorrnax,

" a citizen of the United States, residing at Detroit, county of Wayne, Stateof Michigan, have invented a certain new and useful Improvement in Abrading-Shoes for 'lruing Up Car-"hecls; and I declare the following to be a full, clear, and exact description of the that side which is intended to lie next adjacent to the wheel with a number of pockets or openings or cavities, into some of which is forced an abrading substance, and the exposed surface of the abradiug substance is finished to a shape which in one direction is archedand in the other direction corresponds to-the face of the wheel "in the form which it is desired the wheel to remain.

The drawing shows the grinding-shoe.

Aindicates a shoe arched on its outer or back contour to correspond to the brake-head with which it is to be employed and provided witlra lug B, by mcans of which it may be attached to the ordinary brake head in the same way that a brake-shoe is attached. This side -or face of the shoe may be varied in shape to correspond with the special form of brake-head with which it is to be employed. The inner face, or that face which is intended to be used for grinding, is arched between the ends a and b and is provided with severalcavities, and of these cavities a number, ass 0 '0 are filled with abrading material packed, pressed, or cemented therein and with the inner face of the-abrading material shaped so that a line across the shoe from d to d will conform to a line across the wheel.

As shown inthe drawing, this line would conform to a wheel that is adapted to run in what is known as the grooved rail. One or more of the pockets 6 e are left vacant or unfilled with abrading material and are preferably 5 provided with holes 71 71, through which dust or dirt that may gather in the pockets e 6 can escape freely.

13y using, a number of pockets filled with abrading material I produce a number of 6 sharp or-seraping edges where the wheel engages'the edge of the abrading material, and this not onlyserves to clean the wheel from any dirt that may have gathered upon it, but serves, to grind it more rapidly than would a 6 block filled with a single mass of grinding material. Inasmuch as-the abrading material is harder than the shell of the shoe and will wear longer than the shell of the shoe, which is generally 7 of cast-iron and generally soft when compared either with the abrading material or the wheel which is chilled, there is always a sharp scraping edge to the abrading material and to the cross-walls of the section which con- 7' tain it.

1. An abrading-shoe adapted to be used for trning up car-wheels, having in combination terial and provided with clearance-holes, substantially as described.

2. In an abrading-shoe adapted to be used for truing up car-wheels, th e combination of 'a shell provided with a plurality of cavities adapted to be filled with abrading material, blocks of abrading material set therein, cavities intermediate the blocks, provided with openings whereby accumulated material may be discharged, substantially as described.

v 3. In an abrading-shoe adapted to be used for trning up' car-wheels, the combination of a shell, abrading material set therein, and clearance-holes between adjacent portions of ametallic shell and a filling of abrading ma- 8Q the abrading material, substantially as de 5 

